Effects of luteolin 7-glucoside and its aglicone luteolin in liver lipid metabolism and plasma lipoproteins

• Published in: Planta Medica
• Main Authors: Oliveira, AR, Machado, C, Sá, C, Azevedo, M, Pereira-Wilson, C
• Format: Conference Proceeding
• Language: English
• Published: 30.10.2014
• ISSN: 0032-0943; 1439-0221
• DOI: 10.1055/s-0034-1394877

Flavonoids as luteolin (L) and luteolin-7-glucoside (L7G) are polyphenols abundant in human diet, and are present in vegetables such as celery and green pepper; being particularly abundant in herbs of the genus Salvia (family Laminaceae). These compounds have been associated with various biological activities including modulating blood cholesterol levels, and lipid-lowering properties [1]. In the present study, we fed rats with standard chow supplemented with L7G (2 mg/kg), and found that this compound modulates lipid metabolism in the liver through induction of PPARα and CPT1, important β-oxidation regulators, while decreasing mRNA levels of HMGCoA reductase, the limiting enzyme cholesterol endogenous synthesis. These effects induced by L7G could prevent fatty liver disease and dyslipidemia. In agreement with this, diet supplementation with L7G decreased total and LDL cholesterol levels, improving plasma lipid profile in healthy rats. Although L7G is the form in which this compound is most abundant in nature, there are reports of low bioavailability of flavonoids and particularly of the glycosylated forms that are believed to undergo deglycosylation upon intestinal absorption. In order to compare effects of both, luteolin and his glicone, luteolin-7-glucoside, we tested them in vitro, using HepG2 cell line. The results show that not only treatment with L7G, but also with L increase PPARα which gives the first insights on the effect on β-oxidation regulation by both L and L7G in human hepatocytes; and show that both compounds, in vitro, have comparable effects at this level. Acknowledgements: This work is supported by national funds by FCT – Portuguese Foundation for Science and Technology, under the project PEst-OE/AGR/UI4033/2014. References: [1] M. Azevedo, Ç. Camsari, C. Sá, C. Lima, M. Fernandes-Ferreira, and C. Pereira-Wilson, (2010) Ursolic acid and Luteolin-7-Glucoside Improve Lipid Profiles and Increase Liver Glycogen Content throgh Glycogen Synthase Kinase-3, Phyther. Res., vol. 224, no. 2009, pp. 220 – 224.